By rosebell
As an indication of advance on Line 3 and Corridor 5 in partnership with Tata Projects and Chennai Metro Rail (CMRL),Australian tunneling equipment manufacturer Terratec has reported two tunneling landmarks on Phase II of the Chennai Metro project in the Indian state of Tamil Nadu.
Excavating a tunnel from Kolathur Ramp to Kolathur Station was done by Terratec’s earth pressure balance machine (EPBM) at Kolathur on Line 3.
Considering a shallow overburden of 1.8m, a gradient of -3.8%, and excavation beneath a busy urban corridor, the work was being carried out under what the project team describes as technically challenging conditions.
These factors have required extensive ground-protection measures, noted the company.
In order to progressing a drive towards Srinivasa Nagar, in a separate development at Kolathur Station, another tunnel boring machine (TBM) supplied by Terratec was launched, whereas this section of the alignment passed through mixed Grade-4 and Grade-5 rock and incorporates a tight 230m radius curve.
While the advance so far was in line with expectations for both safety and engineering performance, starting up the new TBM coincided with a breakthrough by another machine at the same station, resulting in two TBM-related milestones occurring at once.
They noted that community engagement and environmental management measures are in place to limit disruption in nearby residential areas, while maintaining what they describe as a strong safety record on site.
With the aim of easing traffic congestion, Phase II of the Chennai Metro is planned to add close to 119km of new track and about 128 additional stations.
SupplYING tunnel boring machines, raise boring rigs and microtunnelling systems, Terratec has previously provided equipment for metro schemes in Delhi, Lucknow, Pune and Mumbai.
